Two-cycle engine



Aug. 16, 1932. H. B. GREENING ET AL TWO-CYCLE ENGINE Filed Feb. 21, 1929 I nlfeniors Patented Aug. 16, 1932 I UNITED STATES PATENT orsice HERALD B. GREENING, oF n MILroN, ONTARIO, CANADA, AND JAMES w. GALLowAY, or .nn'r aorr, MICHIGAN, ASSIGNORS T0 eALLow Y nnernennrne COMPANY LIMITED, or HAMILTON, ONTARIO, cAnAnA v I Two- YCLE ENGINE Application filed February 21, 1929. Serial No. 341,728.

. The principal obj ectsof this invention are, to increase the efliciency'ofthe two cycle type of internal combustion engine by effecting a thorough scavenging of the cylinders and ensuring a complete charge of carbureted air.

The principal features of the invention c onsist'inthe arrangement of a valving element supported by each of the piston; in a pair ofcylinders connected by a common combustion head, saidvalving elements being operated by the transverse swinging movement of the connecting rod or crank.

In the drawing, Figure 1 is a longitudinal midsectional view of a pair of cylinders of an. engine constructed in accordance with this invention. t

Figure 2. is a cross sectional view .on the line 22 of Figure l. i

Figure 3 is a cross sectional view on the line 33 of Figure 1.

In the operation of two cycle combustion engines there-has been an existent fault which many have endeavored to overcome, namely, the difiiculty of expulsion of the products of combustion which causes the following charge of combustible fluid to be less effective than that in a four cycle engine.

It has been proposed to increase the efiiciency of the two cycleengineby arranging the cylinders in pairs with one piston operating slightly in advance of the other in order to open the exhause port prior to the opening of the intake-:and it haszalso been proposed to combine with. the piston of a two cycle .engine a valving element operated by the crank movement and it-is the purpose of this invention to so combine these featuresas to produce a further. improvement in the operation.

In the construction herein shown the cylinders 1 and 2 are connected at their outer ends by a common combustion chamber 3.

The cylinderl is provided with an exhaust port 4: arranged intermediate of its length i and a cylinder 2 is provided with an intake port 5 arranged intermediate of its length.

Pistons 6 and 7 are arranged in the cylinders 1 and 2 respectively and each of these pistons is provided with a valving element here shown in the form of sleeves 8 and 9 which encircle the pistons with a snug-slide ing fit and said sleeves engage the cylinder walls in a piston fit.

A sleeve 8 is provided'with a port 10 which is adapted'to co-operate with the exhaust- LII:

port l in the cylinder 1 and the sleeve 9 is provided with a port 11 adaptedto co-operate with the intake port 5 of the cylinder 2.

Each of the valving elements is provided with a lug extension 12 which is operatively engaged by anarm 13 extending from the connecting rod 1% in the direction, of the swinging movement of said rod.

It will be understood that, as the crank shaft revolves it reachesa point in its downward throw where there is very little downward movement of the piston but in such 7 position of the crank the continued movement swings the connecting rod through a considerable arc while the piston is practically stationary.

The piston sleeves are so arranged on the pistons that when the main crank 15 swings in its downward travel the pistons move below the port openings in the cylinder, while the sleeves carried by said pistons still retain the ports closed.

The transverse swinging of the connecting rod, which produces very little longitudinal movement of the piston in the cylinder does however operate the extension arm 13 engaging the lug 12 to move the sleeve very rapidly.

The ports in the sleeve 8 are arranged to open the exhaust port 4 in advance ofthe opening of the intake 5.

The ports 11 in thesleeve 9 are so arranged that the intake port 5 is retained closed: althoughthe top of the piston has moved below the intake port and the continued downward movement of the piston brings the ports ll into alignment with the intake port 5 following the opening of the exhaust port in the other cylinder. V

The combustible gases are fed to the cylinders under pressure and flow into the cylinder 2 at the bott in end, forcing the burnt gases upwardly and through the common combustion head 3 to the cylinder 1 from the bottom of which said gases are-exhausted.

- The following ofthe burnt gases in this manner ensures a thorough scavenging of the cylinders.

flow into the inlet cylinder after the exhaust has been closed.

This arrangement results in the maximum volume of carbureted air being forced into the cylinders. 7 g

7 It will be seen that with the cylinders arranged in pairs with their centers in the plane of the crank shaft any desirable number of pairs of cylinders may be grouped in radial arrangement around the crank shaft.

This type of engine described may be operated through theinjection of carbureted air, or it may be operated by admit ting air to'the cylinders under pressure with'a fuel introduced in fluid form on solid injection.

What we claim as our invention is z- I.

1. In a two cycle multiple power cylinder engine having a crank shaft provided with pair of cranks one in advance of the other, a pair of cylinders aligned with the crank shaft and-connected at theouter ends by a common combustion chamber, one of said cylinders having an exhaust port and the other of said cylinders having an intake port, con neeting rods and pistons operatively connected with said crank shafts and positioned thereby one in advance of the other, a sleeve surrounding each of said pistons, each having ports therein adapted to co-operate with the port of the respective cylinder, and means operated from the respective connecting rods for operating said sleeves whereby the advance movement of the connecting rod in the exhaustcylinder is utilized to close said exhaust port prior to the closing of the inlet port by the-movement of the other connecting rod.

In a two-cycle engine, the. combination of paired power cylinders aligned with the crank shaft one of said cylinders having an inlet port and the other cylinder having an exhaust port, said cylinders having a common combustion head permanently connecting same and pistons arranged therein and operating one in advance of the other, means operable with said pistons and movable in relation thereto for respectively controlling the exhaust and inlet of said cylinders, and operating members connected with the connecting rods of said pistons at a point below their pivotal connection therewith and extending in planes parallel to the planes of reciprocation of the connecting rods and operatively connected with said movable means whereby the advanced movement of one connecting rod over the other is utilized to impart an advanced positioning to the respective operable control means relative to the other.

3. In a two cycle engine the combination of paired cylinders alignedwiththecrank shaft having a common combustionhead and pistons arranged therein and operating one in advance of the other, sleeves in said cylinders for controllingthe inlet and exhaust thereof, said sleeves having sockets in alignment with the plane of-rec-ip-rocation of the respective connecting rods and operating members connected with the connecting rods of said pistons and'extending in planes parallel to the planes of reciprocation of the latter:and engaging: the wall oftthe sockets'of the sleeves in operating contact.

4. In a two :cyclev engine-thewcombinaition of :paired cylinders aligned :with the crank shaft having a common.'combustionhead:and

. pistons arranged therein'anda operating one in advance of the other, :meansoperable. with said pistons and movable in relation; thereto for control-ling theexhaust;and.inlet of said cylinders, said means being formed Withsock; ets and rigid studsextending transversely from the. connecting rods in; the plane :of re ciprocation. of the latter, saidistudsrhaving their outer ends rounded and; extendingrinto the respective sockets of'said operablo;means for actuating the same.

'5. In a two-cycle multiple cylinder'engine, the combination of paired power cylinders aligned with the crank -shaft,one ofsaid' cylinders having an inlet .port :andethe-other cylinder havingan exhaust port, said .eylinders having a common combustion headipermanently connecting same and, pistons. ;ar-

ranged therein and operatingone inadvance of the other,-means operable Withsaid pis-' tons and movable in relation thereto forrespectively controllingasaidexhaust and inlet of said cylinders, and means operatively connecting the connectingyrods of.:said-;-pistons with said respective. operableacontrolling means for actuating the same whereby the lead of one connectingrodoventhe FOthGI effects the advance movement of. the: respec tive controlling means'relativerto' the other to close the exhaust port of the one -.cylinder prior to the closing ofathe inlet of the-other cylinder.

HERALD .B. GREENING. JAMES W. GALLOWAY. 

